Beard had previously played baby parts in many films before signing a five year contract to play in Our Gang. In contrast to Farina, the character he replaced, Stymie was a slick-tongued con-artist who was always self-assured, nonchalant, and ready with a sly comment as well as clever ideas to solve the problems he faced. Stymie could also offer sound, commonsense advice that helped resolve the dilemmas of his white playmates. The character's trademark was a bald head crowned by an oversize derby hat, a gift to Beard from comedian Stan Laurel, who had also worked under Our Gang creator Hal Roach. Stymie is the only Our Ganger who both replaced one of the original gang members (Allen "Farina" Hoskins) and was in turn replaced by one who would stay on until the series disbanded, Billie "Buckwheat" Thomas.

The name "Stymie" was provided by Our Gang director Robert McGowan, who was always frustrated ("stymied") by little Matthew's curious wanderings around the studio; the character was originally to be named "Hercules". McGowan would later recall that Stymie was his favorite of all the Our Gang kids. The then five-year-old Beard came to the series a year after the transition from the silent/early talkie era Our Gang. He had the exclusive distinction of being with the gang from "Miss Crabtree" talkies of the early 1930s, through the mid-thirties transitional period, up until the era of the more familiar group of Spanky, Alfalfa, and Buckwheat, who would ultimately replace Stymie in 1935.

Beard's paycheck was used to help support his East Los Angeles family, including thirteen brothers and sisters. After Beard renamed his younger brother Bobbie "Cotton" (which was also used as Bobbie's Our Gang character name), his parents allowed him to name all of the rest of his siblings as they were born. He named one "Dickie" after his best friend, child actor and Our Gang kid Dickie Moore. Four other members of the Beard family would appear in the Our Gang comedies:

Falling into drug use and street life, Beard became addicted to heroin, and spent most of his early adult life in and out of jail because of it.[2] In the 1960s, he checked himself into Synanon, a drug rehabilitation facility in Los Angeles, and successfully ended his heroin use.[2] After leaving Synanon, he made a small comeback, appearing in small roles in feature films and episodes of television shows such as Sanford and Son,[3] and Good Times where he had a recurring role as "Monty".[3] In 1978, he appeared in the movie The Buddy Holly Story as a member of the backstage crew at the Apollo Theatre, wearing his trademark bowler hat.[3]

Beard traveled around the country, giving lectures on drug-abuse awareness.[2]

Beard suffered a stroke two days after his 56th birthday in 1981, sustained head injuries from falling down a flight of stairs, and died of pneumonia on January 8, 1981. He was residing in Los Angeles, California at the time of his death. He is interred in the Evergreen Cemetery, Los Angeles. He was buried with the famous bowler hat he wore all his life, from his Stymie days.